Unpackaged semiconductor dice are used to construct multi-chip modules, field emission displays and other electronic devices. With an unpackaged die, electrical connections must be made between bond pads on the die and other electrical components of the electronic device. For example, a die can be mounted on a printed circuit board (PCB) or lead frame and electrically interconnected to conductive traces.
One method for electrically connecting a semiconductor die to an electronic device such as a PCB, is sometimes referred to as "flip chip mounting". With this method the die is placed circuit side down on the electronic device and bumped bond pads on the die are bonded to solder pads formed on the electronic device. Another method of electrically connecting a die to an electronic device is sometimes referred to as "chip and wire" technology. With this method the die is back bonded to the device and flat bond pads on the die are wire bonded to corresponding bonding sites on the device.
These methods work satisfactorily for most applications. However, in some applications it may be necessary to provide an electrical connection between the die and an electrical component that is on a different plane or is angled (e.g., orthogonal) with respect to the plane of the die. For example, a field emission display (FED) can include conductive traces that electrically connect various elements of the display. Many of the conductive traces are located on different planes, or levels, than the semiconductor dice used to construct the display. In these cases an interlevel connection is typically made between the dice and the conductive traces using metal filled vias.
It would be advantageous to be able to more easily form an electrical path between a semiconductor die and corresponding electrical components such as conductive traces that are located on different surfaces, or planes, than the die. This would eliminate the need for interlevel vias and would simplify the construction of some electronic devices.
Another situation that occurs in the construction of electronic devices, such as field emission displays, is that a semiconductor die must sometimes be located in the interior of a sealed package. For example, field emission displays can be constructed as a sealed package evacuated to a pressure of 1.times.10.sup.-6 Torr or less. A baseplate component of the field emission display can be constructed as a semiconductor die mounted within the sealed interior of the package. Here, it is necessary to make multiple electrical connections through the sealing member to the die. It would be advantageous to be able to make these electrical connections without the requirement of complicated electrical connectors or connectors that compromise the sealing member.
In view of the foregoing, it is an object of the present invention to provide an improved method for forming an electrical connection to a semiconductor die. It is another object of the present invention to provide an improved method for constructing field emission displays. It is a further objection of the present invention to provide an improved method for making an electrical connection between a semiconductor die and electrical components located on a different surface or plane than that of the die. It is a still further object of the present invention to provide an improved method for making an electrical connection between a semiconductor die mounted in a sealed space and corresponding components outside of the sealed space. Other objects, advantages and capabilities of the present invention will become more apparent as the description proceeds.